Senior Data Scientist

Organization & Team 

Microsoft’s Identity organization secures hundreds of millions of daily signins and protects missioncritical services at global scale. We’re hiring a Senior Data Scientist to advance adaptive threat detection at the edge and resilience of origin services—designing models that detect and mitigate abusive patterns in real time, improving customer safety and service reliability. 

Role Overview 

Every day, hundreds of millions of people rely on Microsoft services such as Microsoft 365, Azure, Xbox, and Outlook.com. Behind the scenes, Microsoft’s Edge team works continuously to protect those users from account compromise, fraud, and abuse. Our data science team sits at the core of this mission, building and operating machine-learning–driven protections that stop malicious actors at global scale. 

In this role, you will lead end-to-end data science efforts, from signal design and feature engineering through model training, online scoring, and experiment evaluation. You will work across two strategic problem areas: 

1. Behavior-driven intelligent blocking: Learn patterns from authentication and access signals to automatically reject malicious activity such as password spraying or account enumeration, while minimizing false positives. 

1. Volume-driven origin protection: Identify and throttle anomalous traffic surges to protect upstream services from degradation and ensure fair usage. 

You will dive into terabytes of data to understand an ever-evolving threat landscape, turning a blank canvas of signals into robust, production-ready detections that balance strong security with a seamless user experience. You’ll partner closely with applied scientists, software engineers, and product leaders across Identity and edge services to ship measurable, real-world protection improvements. 

If you’re passionate about big data, machine learning, and fraud detection—and motivated by the opportunity to protect millions of users as part of a mission-driven, highly collaborative team—this role offers both scale and impact. 

Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond.

• Design, build, and operate machine-learning–based detections to prevent fraud and abuse across Microsoft Identity services. 

• Lead signal and model design by defining features, labels, heuristics, and training approaches using supervised and unsupervised techniques. 

• Analyze large-scale authentication, access, and traffic data to identify emerging abuse patterns and translate them into automated detections. 

• Productionize models for low-latency online scoring, implementing guardrails, dynamic thresholds, and safety mechanisms to minimize customer impact. 

• Design and analyze experiments (A/B tests, holdouts) to evaluate detection effectiveness and quantify tradeoffs such as false positives and false negatives.